The proposed work is focussed on the design and development of new synthetic methods and reagents and their application to the synthesis of the tumor promoters and inhibitors of the tigliane, daphnane, and ingenane series and the synthesis of quadrone and related potential antitumor agents. The synthetic component of this effort is directed toward an improvement of methodology for the preparation of complex, polycyclic compounds while the biological component is directed largely toward the development of an understanding of the mechanism of action of tumor promoters.